Salinity is one of the most important abiotic factors affecting growth, metabolism, immunity and survival of aquatic species in farming environments. As a euryhaline species, the Asian sea bass (Lates calcarifer)can tolerate a wide range of salinity levels. A 56-day research was performed to examine the effect of acute salinity on the expression of growth, stress, immunity osmoregulation genes in Asian sea bass (Lates calcarifer). Fishes were allocated into 12 circular fiberglass tanks of 300 L in 4 treatments of fresh water and salinities of 15, 35 and 50 ppt and each dietary treatment replicated in triplicate. Fishes were handfed at 4/5 % of their initial biomass twice. Sampling were made at five different times at 6, 24, 48, 72 and 120 hours after the start of treatment. The results showed only in salinity of 50 g/L with the passage of time up to 72 and 120 hours the mRNA expression of AQP1 significantly increased and decreased respectively (p<0.05). The mRNA expression of AQP3 at 15 g/L salinity up to 24 hours significantly increased. At salinities of 35 and 50 g/L until 72 hours, the expression level of AQP3 decreased (p<0.05). After 48 hours at 15 and 35 g/L salinity a significant increase in the mRNA expression of interleukin was observed, but the level of the mRNA expression of interleukin decreased at 50 g/L salinity (p<0.05). At 72 and 120 hours after treatment in salinity of 15 and 35 g/l, an increase in the mRNA expression of interleukin was observed (p<0.05). In salinity of 35 g/L and 50 g/L, with the passage of 6 hours, in the IGF-I mRNA expression decreased and increased, respectively. At 15 and 35 salinities, after 72 hours, a decrease in the IGF-I mRNA expression was observed (p<0.05). At 35 and 50 g/L salinity, after 120 hours, the IGF-I mRNA expression decreased and increased, respectively (p<0.05). This study shows that a acute salinity affects on the expression of growth, immunity, osmoregulation genes.